Vegetable textile material and process for producing same



Patented Nov. 19, 1929 UNITED STATES PATENT OFFICE LEON LILIENFELD, F VIENNA. AUSTRIA No Drawing. Application filed July 23, 1924, Serial No. 727,808, and in Austria April 4, 1924.

This invention relates to a new process for improving the quality of vegetable textile materials and particularly cotton, (or a fabric containing such a fibrous material).

According to the invention, very valuable properties are conferred upon woven or spun products of vegetable origin by treating them with a mono-halogen derivative of a fatty acid in the presence of an alkali.

The results of this process are: either a high degree of transparency and a silky lustre of a brilliancy hitherto unattained, or a more or less elastic or stiffening finish, or both lustre and finish.

partly on the concentration and the proportions of the reagents, partly on the duration of the treatment, partly on the temperature, partly on the nature and previous treatment of the fibrous material and partly on whether and at what stage in the process the material under treatment is stretched. When stretching is not employed substantially no silky lustre is produced, but instead the cotton fabric or yarn assumes a wool-like appearance and feel respectively. a

The process consists in treating a spun or woven fabric consisting of a vegetable fibrous material, particularly cotton, or a fabric containing such a fibrous material, with a monohalogen-fatty acid or with a salt or derivative thereof (for example an ester) in the presence of an alkali. The spun or woven v goods may be treated with alkali andhalogen-fatty acid at the same time or in succession in either order.

As alkalies, there come into consideration in the first place the caustic. alkalies. With alkali sulphides, however, results may be obtained, though these are less satisfactory.

All vegetable fibrous inaterials, such as linen, flax, hemp, ramie, jute, and particularly cotton, in the form of pure vegetable fabrics (for example'pure cotton fabrics) or of mixed fabrics or in the form of yarns in skeins or cops or of warps may be successfully treated according to the invention.

The textile material consisting of or con: taining vegetable fibre may be treated by the present process either in crude state or after lVhich of these effects is produced depends a preliminary treatment (for example boil ing, or heating under pressure with a solution of sodium carbonate or dilute caustic alkali or botl1),the textile material being previously moistened or not asdesired, with or without 5 previous extraction of the fatty matter, unbleached or bleached by means of an oxidizing or reducing bleaching agent, mercerized or not mercerized. It may also previously be prepared in known manner by means of a hydrolyzing or gelatinizing agent, for exa1nple, a strong mineral acid such as sulphuric acid of 49 to 60 Baum gravity or phosphoric acid of to 57 Baum gravity, or hydrochloric acid of 24 Baum gravity, or nitric acid of 43 to 46 Baum gravity or more, or an ammoniacal solution of cupric oxide, or with a cold or hot solution of calcium thiocyanate or other thiocyanate. The preliminary treatment may consist in a combination of two or more of these methods.

In the present invention the working conditions may be varied within wide limits. It is therefore not to be limited to the details of the description hereinafter given of the manner in which it is carried out.

The following methods of carrying out the process are given by way of example The first consists in treating the spun or woven goods .first with a solution of a caustic alkali and then with a monohalogen derivative .of a fatty acid, such as 'monochloacetic acid. The textile fibrous material may be treated with the alkali solution in various Ways, for instance by immersing or soaking the material in a small or large excess of alkali solution; or by immersing or soaking the material in the solution and removing the excess of the alkali solution by squeezing, centrifuging or the like; or by impregnating in an impregnating mill or jigger or the like; orby padding by means of smooth or engraved rollers in a padding machine; or by coating by means of closely engraved rollers in a Rouleaux machine in which case a suit- 95 able thickening medium is preferably used; or by spraying or by any other known method. I

As the alkali solution there may be used for example caustic soda solution of 10-50 100 or after having derivative thereof may been per cent strength. Caustic soda solutions of from 12 to 40 per cent strength have been found to be very suitable.

The quantity of the alkali solution which is incorporated in the spun or woven fabric or the quantity which is to be retained by the fabric may vary within very wide limits. Thus, for example, excellent results are obtained with an amount .of twice or. of ten times the weight of the textile material. As a rule an amount of from two to four times the weight of the textile material is found to be sufficient.

The temperature of the alkali solution may be selected from a wide range. According to the strength of the solution useful results are obtained at 10 C. and from that up to +50 C. In the case of alkali solutions which are not too weak satisfactory results are usually obtained at room temperature.

In order that the alkali solution may penetrate the fibres thoroughly and that the lustre may be improved the spun or woven goods may be allowed to pass between rollers during the treatment with the alkali solution or the material may be subjected to a high pressure in some other manner. If desired alcohol may be added to the alkali solution.

The textile material which has been treated with the alkali solution, immediately or after standing (ripening) for a short or long period (say 3 hours to 3 days) at or above room temperature is treated in the wet condition been previously partially or completely dried, with a free monohalogen derivative of a fatty acid or with a salt or derivative (for example an ester) thereof. The monohalogen fatty acid or its salt, preferably alkali salt, may be brou tact with the spun or woven goo been previously treated with alkali solution, in the form of a dilute or concentrated solution or of a supersaturated solution (for instance a pasty mass of crystals of an alkali metal salt) or of a suspension, or even in the solid form. As a solvent there may be used water or alcohol or a mixture of water and alcohol or any other solvent; In order to insure uniform distribution of the halo gen fatty acid, or salt thereof, there may be added to the solution or suspension if desired a suitable binding or thickening agent, such as starch, dextrine, British gum, albumen or the like.

The monohalogen fatt acid, or the salt or lie added in various to thespun or woven goods which have treated with the alkai solution. The goods may be soaked in the solution or suspension of the acid or of its salt in the cold or warmed to a temperature of -for example 50-100 C. (in which case, if desired, any excess may be removed by squeezing or cantrifuging); or they may be coated with 1t; or a solution or suspension of the halogen ways ht into con-' s which have dried. It may also poration between one or more pairs of rollers,

or otherwise subjected to pressure.

For the treatment with the monohalogen fatty acid there may he used any suitable de vice known in the cloth finishing or textileprinting industry.

There is-in practice no limit to the quantity of the halogen fatty acid'or the salt, or derivative thereof, which may be used. As a rule, to which however the invention is not limited, it is-suflicient to use not more than one or at the most two molecular proportions of monohalogen fatty acid for each molecule of caustic alkali. In most cases much smaller quantities, for instance 0.3 to 0.75 molecular proportion or even less, of the monohalogen fatty acid for each molecular proportion of ing if desired, are then either directly washed C.) for a short ori or, advantageously, treated with a cold or warm solution of an inorganic or orgamc acid or of an acid salt, or' of an ammonium salt, or of some other salt, or with a tannin solution, or with a formaldehyde solution or with any precipitating agent or mixture of precipitating agents known in the viscose industry or. in the ammoniacalcopper-oxidecellulose industry, and is then washed and be steamed before or after washing.

All the subsidiary operations usual in mercerization or proposed in connection therewith may also be employed in the present process, for instance lustering, pressure, mechanical beating and the like.

For the attainment of a high silk-like lustre, stretching of the textile fibrous material is essential. It may be stretched either during all the steps, that is, commencing with the impregnation with the alkali solution, up to the washing and dr ing process. Or it may be stretched only urin the action of the alkali solution or of they alogen fatty acid; or the spun or woven'goodsmay be stretched after the impregnation with alkali solution and kept halogen fatty acid and during the treatment with acid, salt, or the like and during the washing and finaldrying. Or they may be stretched during the action of. the

stretched only after the action of the alkali solution and halogen fatty acidfor the treatment with the acid or salt and the washing ment with alkali solution, and with the acid or salt and the final washing, but not during the action of the monohalogen fatty acid.

The second method of carrying out the process consists in reversing the order of the operations of the first method, that is to say, the textile fibrous material is first brought into contact with the monohalogen-fatty acid or its salt or derivative and then introduced into the solution of alkali, or impregnated, coated or sprinkled or sprayed therewith. As the halogen fatty acids exert no action on the fibrous material in the absence of alkali, the treatment with alkali solution may follow at leisure the treatment with the halogen fatty acid. After the material has been brought into contact with the alkali solution the halogen fatty acid must be allowed to react for sometime, and the action may proceed at or above room temperature. As regards the other workingconditions, such as the relative proportions of the reag-nts, temperature, duration of the reaction, tretching, finishing of the goods and the llku the indications given in the description of the first method of carrying out the process are equally applicable.

The third method of carrying out the process consists in treating the textile fibrous material with a solution of the halogen fatty acid in alkali solution. This method, on account of the small power of resistance of the monohalogen fatty acid to alkali hydroxide, is the least to be recommended. If it is desired to employ it, it is necessary to work either very quickly or at low temperatures (below 0 C. for example) or to use dilute solutions of alkali.

By an appropriate selection of the conditions of working there may be obtained by the process silk-like effects which are far superior to those which may be obtained ac-' cording to the usual inercerizing processes. In this case, if the quantities of the reagents are not,excessively large and if the duration of the action of the monohalogen fatty acid is not carried too far, and if in the case of a somewhat prolonged reaction the temperature employed is not unduly high, no stiffening, or substantially no stiffening-of the fabric or yarn occurs. It acquires on the contrary, besides the silk-like lustre, a valuable finish and elastic feel. The silk-likelustre may be materially enhanced by one or more repetitions of the process. Only by substantially increasing thev uantities of reagents used, particularly in t e ca'seof the monohalogen fatty acid, and prolonging the duration of the action, especially at rather high temperatures, is a stiff finish obtained. Ex-

perience shows that when there are used al-.

kali solutions of low or medium strength, caustic soda solutions of from 12 to per cent strength for example, even by the action of large quantities of monohalogen fatty acid, and even when the reaction is prolonged there is much less tendency towards the formation of a stiff finish than when strong solutions to per cent strength of caustic soda solution for instance) are used.

The dressing may further be increased by adding some cellulose, such as sulphite-cellulose or linters in a finely divided form, or mercerized cellulose, or a cellulose hydrate, to'the alkali solution (if desired, with the aid of a thickening agent) or to the solution, paste, or magma of the halogen fatty acid or salt thereof.

The process according to the invention is also suitable for obtaining pattern effects, for which purpose the following methods of procedure may be considered by way of example 1) Before the treatment with the solution of an alkali a pattern is printed or stencilled on the woven fabric by means of a reserve paste which prevents absorption of the alkaline solution either mechanically or chemically. Appropriate reserve agents are, for example, albumen, gum, acids (such as acetic acid, citric acid, tartaric acid or an inorganic acid), alum, aluminium sulphate, ammonium sulphate or other salt. The fabric is then treated with an alkali solution and a monohalogen-fatty acid in the manner described in the first method of carrying out the process. This modification of the process gives rise to a lustrous pattern on a dull background, or vice versa.

(2) The alkali solution, mixed with an appropriate thickening medium (such as starch, denatured albumen, a cellulose hydrate soluble in alkali, alkyl or oxyalkyl derivative of cellulose soluble in alkali or in water, a cellulose ether of a monohydroxy carboxylic acid, or the like) is printed on the fabric in the form of any desired pattern, and the fabric is then treated with a halogen fatty'acid in the manner already described. The effects obtained are similar to those in (1).

(3) The fabric, after being treated with alkali solution and, if desired, dried, is printed with a reserve which'mechanically or chemically prevents the reaction between as described in the first method of procedure, treated with an acid or a salt, and dried. This method of working produces very' lustrous effects ona less lustrous back-ground, or vice versa.

I (4) Pattern-effects may also be obtained by impregnating the fabric with a solution of an alkali, as described in the first form of the process, and then, after previously drying if desired. printing it with a monohalogen fatty acid or a salt thereof, dissolved or suspended in a suitable thickening medium (such as British gum, starch, or dextrine) with or without the addition of a dyestuff, and then finishing the fabric as described in thefirst form of the process. Very lustrous effects are obtained on a less lustrous background.

(5) A monohalogen fatty acid or a salt thereof in the form of a solution or suspension is'printed on the fabric with the aid of v a. thickening medium. after which the fabric is exposed with or without drying to the action of caustic alkali. The results obtained are similar to those of and (4).

The following examples illustrate the invention, the parts being by weight (a) Bleached or unbleached cotton fabric or yarn is treated with soda solution of 25-40 per cent strength at room temperaturefor a period of from 5 minutes to 12 hours and the excess of soda solution is removed by squeezing or centrifuging so that the fabric retains about 2 to 3%; times its weight, or

any other desired quantity, of caustic soda solution. The material impregnated with the soda solution either immediately after the impregnation or after being left to itself for from 3 to 72 hours, is then treated with sodium monochloracetate, preparedfor example by dissolving 100 parts'of monochloracetic acid in 100 parts of water or in a solution of British gum of 20 to 25 per cent strength and adding to the solution about 90 parts of powdered sodium bicarbonate, in small portions whilst shaking or stirring. After addition of this quantity of bicarbonate and after the-carbon-dioxide has escaped, a' suspension of sodium chloracetate crystals remains; this may be used as such, or after warming for a short time, for example to 50-60 C. during which it is converted into a solution. The yarn or fabric (carrying theNaOH solution) may either be impregnatedwiththesuspension or solution of sodium chloracetate or coated with it on one or on both sides, or the solution of the chloracetate may be rolled on or into the textile material. The quantity of sodium chloracetate which is to be incorporated with the fabric or yarn impregnated with caustic soda solution is subject to variation between wide limits. For .reasons of economy however it is desirable to usenot more than from 1 part of longer time (for example, 12 hours) with the sodium chloracetate it is introduced either into dilute sulphuric or acetic acid;- for instance, of 1020 per cent, or into a solution of ammonium chloride or ammonium sulphate of 204-30 per cent strength, or into any other precipitating bath customary in the viscose industry. It is allowed to remain in it for a short time (for instance 5 minutes) or for a longer time (for instance seveal hours), and is then washed'arid dried. he fixing agent may also be applied to the fabric by sprinkling, spraying, or the like. Or the cotton material iswashed after it has been treated with alkali solution and sodium monochloracetate and then treated with the fixing agent, washed and dried. It may also be only washed and dried.

During the above operations the fabric or solution or with the sodium chloracetate.

the sodium chloracetate, and of the treatment with an acid or salt, if'.any-. The textile fibrous material may also be washed in the stretched condition, this having a beneficial effect on thesilk-like lustre.

According to this example there is obtained a high-grade silk-like lustre, and a pleasing, resilient finish; also, if the duration of the action of the alkali solution, or y of the ripening, after the impregnation process, or of the action of the sodium mono chloracetate is prolonged and the quantity of sodium monochloracetate is very large, a

stiff finish is obtained.

(6) The procedure is as. in Example I. (a), with the difference that instead of the sodium chloracetate there is used an aqueous solution of free chloracetic acid of 50 per cent strength for impregnating or coating the material which has been impregnated with caustic soda solution.

(0) The procedure is as in Example I (a) i with the difference that the sodium chloracetate'is prepared as follows: 40 to 70' parts of chloracetic acid are dissolved in 160 to parts of water or of a solution of British gum of 25-30. per cent strength and the solution is treate'tlas in Example I a), with about 36 to 63/parts-of powdered sodium bicarbonate, whereby there is obtained a solution which is liquid at 'room temperathe action of the sodium chloracetate or of the chloracetic acid as the case may be takes place while warm. For the purpose the fabric which has been impregnated with the caustic solution and brought into contact with the sodium chloracetate or chloracetic acid is maintained for a period of from 10 minutes to an hour at a temperature of 50 to 100 (1., for example at 80 C. If the duration of the warming at 80 C. for example is prolonged for an hour or more there is obtained, besides a high-grade silky lustre, a stiff dressing, which may approximate to the stiffness of book-binders linen.

e) The procedure isas in Examples I a) I (1)),1 (c) or I (d) with the difference that instead of the caustic soda solution of 25-40 per cent strength there is used a caustic soda solution of 18-23 per cent strength, for example of 22.5 per cent strength. The finished products exhibit a very fine silk-like lustre.

(f) The procedure is as in Examples I (a), I (c), I (d), or I (e) with the exception that the sodium monochloracetate or the like, pref erably in the presence of British gum, is printed in the form of any desired pattern on the fabric which has been treated with caustic soda solution, and, if desired, dried before being printed.

(a) Bleached or unbleached cotton fabric or yarn is impregnated with a solution prepared as follows, with the addition, if desired, of a thickening medium such as British gum, as described in the foregoing ex amples:100 parts of monochloracetic acid are dissolved in 400 to 900 parts of water and the solution is treated with about 90 parts of powdered sodium bicarbonate. The textile material impregnated with this solution is introduced if desired, after removing the excess by squeezing or centrifuging into a caustic soda solution, of 30- l0 per cent strength left in contact with the solution for a period of from 10 minutes to two hours and then finished as described in Example I (a). The fabric is stretched during or after the treatment with the caustic soda solution. A silk-like lustre is obtained.

(1)) The procedure is as in Example II (a) with the difference that the material is dried before it is introduced into the caustic alkali solution.

' III The procedure is as in any of the Examples I (a) to I (6) with the difference that the sodium chloracetate is prepared in .HThe finished products m y be the following manner: 90 parts of chloracetic acid are dissolved in 60 parts of Water, and neutralized with about 80 parts of sodium bicarbonate which is added in small portions. As soon as the evolution of carbon-dioxide has ceased, 150 parts by weight of alcohol of 96 per cent strength are added whilst stirring, whereby a milky suspension is produced.

The silk effect produced is of a high grade, the finish has an elastic feel.

The procedure is exactly as in any of the preceding examples, with the modification that the material is first treated with a strong sulphuric acid prior to its treatment according to the process herein described. If a sulphuric acid of 49 to 50 Baum gravity be used for this purpose, the treatment therewith may be allowed to proceed at room temperature for a period of from several seconds up to a few minutes and even longer. If a stronger sulphuric acid is used, for example,

of 52 to 54 Baum gravity, then the trea ment must only occupy a few seconds, if the treatment is conducted at room temperature. If however the sulphuric acid be cooled down to 0 C. or below the treatment may continue for a longer period.

Mercerization of the fabric, for example, by means of a caustic soda solution of 10 per cent strength at a low temperature or with a strong caustic soda solution, for example, of 18 to 40 per cent strength, at room temperature, may precede the treatment with sulphuric acid.

The procedure is exactly as in any of the foregoing examples, with the difference that the fabric is previously mercerizedaccording to any known mercerizing process.

Instead of the monochloracetic acid, there may be used with satisfactory results, a monohalogen derivative of a homol0gue of acetic acid, such as a-bromo-propionic acid, a bromo-butyric acid, or a halogen derivative of another organic acid, e. g. bromosuccinic acid.

.calendered, schreinered, or beetled or the like.

Examples for pattern effects by means of a reserve follow as a matter of course.

. wherever the context permits,

- On treatment with a monohalogen derivative of a fatty acid inthe presence ofan alkali, the vegetable fibres are converted into a cellulose ether of an alkali salt of a monohydroxy carboxylic acid in which the cellulose has entered into the hydroxyl group of a monohydroxy carboxylic acid. In case of monochloracetic acid, cellulose ethers of alkali salts of glycolic acid are formed. Whether that conversion of the fibres takes place only on the surface of the fibres or in their deeper parts also, depends partly upon the concentration and amount of the alkali solution, partly on the uantity of the monohalogen-fatty acid use and partly on the temperature.

The cellulose'ethers of alkali salts of monohydroxy carboxylic acids formed as indicated in the preceding paragraph will be converted into acid ethers by immersing the fabric in cold or warm solutions of organic acids, such as acetic acid, or by immersion in cold or warm dilute solutions of inorganic acids, such as dilute sulphuric acid, or by immersing the fabric in a solution of an acid salt or any precipitating agent or mixture of reci itatin a ents known in the viscose P P g industry or in t e ammoniacal-copper-oxidecellulose industry.

On treating th finished fabric with a hot dilute mineral acid or a concentrated mineral acid at room temperature, a decomposition of the ethers takes place. This decomposition ma be brought about, for example, by a hy ro-halogen acid, such as hydrochloric acid, or by sulphuric'acid. These mineral acids when used in the manner described cause the ethers of mono hydroxy carboxylic acids or salts to liberate hydroxy-paraflin mono-carboxylic acids: Upon treating cellulose ether of glycolic acid with mineral acids in the manner above described glycolic acid is liberated. p

The expression textile fibrous material. in the specification and in the claims includes all vegetable fibrous materials, such as flax, linen, hemp, ramie-fibre, jute and articularly cotton and the like, in the form 0? pure vegetable fabrics .(for example pure cotton fabrics) or mixedthe form of yarn in skeins,f cops,-

fabrics or in or warps.

The expression halogen derivative of fatty acid or monohalogenderivative of a fatty acid includes wherever the context permits, the free monohalogen fatty acid or a salt, or a derivative thereof, such as an ester.

The expression cellulose ether of a monohydroxy carbo lic acid includes those cellulose compoun s in which the cellulose has entered the hydroxyl group of a hydroxyparaflin mono-carboxylic acid (possibly with the formation of a lactone or a lactide).

1. As new products, vegetable textile fimean s of a cellulose ether of a mono-hydroxy carboxylic acid supplied from'outside, contain a cellulose ether of a mono-hydroxy carboxylic acid soluble in alkali but not in water.

3. As new products, vegetable textile fibrous materials, which, Without having been finished by means of a cellulose ether of.

glycolic acid supplied from outside,.contain a cellulose ether of glycolic acid soluble in alkali but not in water.

. 4. As new products, vegetable textile fibrous materials which have a silk-like lustre and which, without having been finished by means of a cellulose ether of glycolic acid supplied from outside, contain a cellulose ether of glycolic acid soluble in alkali but not in water.

5. As new products, vegetable textile fibrous materials which, without having been finished by means of a cellulose ether of a mono-hydroxy carboxylic acid supplied from outside, split off a hydroxy-parafiin monocarbox lic acid on decomposition with a hydroalogen acid.

6. As new products, vegetable textile fibrous materials which have a silk-like lustre and which, without having been finished by means of a cellulose ether of a mono-hydroxy carboxylic acid, sup lied from outside, split ofi of hydroxy-para mono-carboxyhc acid on-decomposition with ahydro-halogen acid.

7. As new roducts, vegetable textile fibrous materia s which, without having been finished by means of a cellulose ether of glycolic acid supplied from outside, split. ofi

glycolic acid on decompositon with a hydrohalogen acid.

8. As new roducts, vegetable textile fibrous material which have a silk-like lustre and which, without having been finished by means of a cellulose ether of glycolic acid supplied from outside, split off glycolic acid on decomposition with a h dro-halogen acid. 9. The process of treating vegetabletextile fibrous material which comprises subjecting said material to the action of a monohalogen derivative of a fatty acidin ,the'

presence of an alkali and preserving the textile character of said material throughout said action.

10. The process of treating cellulosic vegetable fibres which comprises subjecting said fibres to the action. of a monohalogen devative of a fatty acid in the presence of hydroxide of an alkali metal and regulating such action so that said fibres do not lose their identity as fibres but "become converted at least in part into compounds of cellulose.

11 The process of treating cellulosic textile fibrous material which comprises subjecting said material to the action of a monohalogen derivative of a fatty acid in the presence of caustic alkali short of complete dissolution of the said cellulosic material, whereby said material becomes in part con-. 0 verted into a compound of cellulose, and thereafter converting the compound so formed into a water insoluble compound of cellulose. 1

12. The process of treating cellulosic textile fibrous material which has its fibres converted at least partially through their diameter into alkali cellulose which comprises subjecting the said so converted material to the action of a monohalogen fatty acid.

13. The process of treating cellu'losic fibrous material which comprises converting the fibres of said material at least in part through their diameter into cellulose ether of a salt of mono-hydroxy carboxylic acid in which the cellulose has entered into the hydroxyl group of said salt, and thereafter converting said salt into the corresponding acid ether.

14. The process of treating cellulosic 3o fibrous material which comprises subjecting said material to the action of a monohalogen acetic acid in the presence of an alkali only to such an extent that the fibres become finished with the cellulose derivative formed from said action.

15. The process of treating vegetable textile fibrous material which comprises subjecting said material to the action of monochloracetic acid in the presence of alkali and regulating the progress of said reaction so as notto destroy the initial character of said material as a textile.

16. The process of treating vegetable textile fibrous material which comprises subjecting said material to the action of a monohalogenderivative of a fatty acid and caustic alkali in two steps and preserving the textile character of said material throughout said action.

17 The process of treating vegetable textile fibrous material which comprises subjecting said material to the action of caustic alkaliand thereafter to the action of a monohalogen derivative of a fatty acid and preserving the textile character of said mate rial throughout the said actions.

18. The process of treating cellulosic fibrous material which comprises subjecting said material to the action of caustic alkali acetic acid, and regulating said actions so that the fibres are not dissolved but merely finished with the cellulose derivative formed from said actions.

c5 19'. The process of treating cellulosic and thereafter to the action of a monohal'ogen fibrous material which comprises subjecting said material to the action of a monohalogen fatty acid in the presence of alkali only to such an extent that the fibres become finished with a cellulose compound resulting from such action and thereafter converting said cellulose compound into a cellulose compound insoluble in water.

20. The process of treating vegetable textile fibrous material which comprises subject: 7 ing said material to the action of a solution containing caustic alkali, thereafter to the action of monochloracetic acid and regulating said actions to such an extent that the fibrous 'materials are not completely dissolved but retain their textile character and thereafter converting the cellulose compound formed by said action into a cellulose compound insoluble in water.

In testimony whereof I aflix my signature. g

LEON LILIENFELD. 

